Doxycycline (Systemic — Ocular Rosacea / Blepharitis)

How it works

Beyond its antibacterial inhibition of ribosomal protein synthesis, low-dose doxycycline exerts an anti-inflammatory effect by inhibiting matrix metalloproteinases and reducing lipase activity that destabilises the tear film lipid layer.

Prescribing in practice

• Doxycycline is contraindicated in pregnancy, breastfeeding and children under twelve because tetracyclines cause permanent dental staining and affect developing bone.
• It is photosensitising, so patients should be warned about exaggerated sunburn and advised on sun protection.
• To reduce the risk of oesophageal irritation and ulceration, doses should be swallowed whole with plenty of water while sitting or standing and not immediately before lying down.

Monitoring

Routine laboratory monitoring is not usually required for short anti-inflammatory courses, but clinical review of symptom response and tolerability guides duration of therapy.

Counselling the patient

• Take with a full glass of water and stay upright afterwards to protect the gullet.
• Use sunscreen and cover up, as your skin will burn more easily.
• Improvement in eye comfort may take several weeks, so persist with the course as directed.

Evidence & guidelines

Sub-antimicrobial and anti-inflammatory tetracycline dosing for meibomian gland dysfunction and ocular rosacea is supported by long-standing ophthalmology and dermatology practice.